Dobby, specially adapted for speedy looms



Dec. 28, 1965 PIAZZOLLA E L SPECIALLY ADAPTED FOR SPEEDY LOOMS DOBBY,

4 Sheets-Sheet 1 Filed Aug. 6, 1963 Dec. 28, 1965 PIAZZOLLA ET AL3,225,792

DOBBY, SPECIALLY ADAPTED FOR SPEEDY LOOMS Filed Aug. 6, 1963 4Sheets-Sheet 2 Dec. 28, 1965 G. PIAZZOLLA ET AL 3,225,792

DOBBY, SPECIALLY ADAPTED FOR SPEEDY LOOMS 4 Sheets-Sheet 5 Filed Aug. 6,1963 INVENTORS Dec. 28, 1965 G. PIAZZOLLA ET AL 3,225,792

DOBBY, SPECIALLY ADAPTED FOR SPEEDY LOOMS Filed Aug. 6, 1963 4Sheets-Sheet 4 United States Patent O 3,225,792 BOBBY, SPECIALLY ADAPTEDFOR SPEEDY LOOMS Giovanni Piazzolla, Via Salieri 6, Milan Italy, andCarlo Villa, Via Giuseppe Mazzini 24, Melzo, Milan, litaly Filed Aug. 6,1963, Ser. No. 300,302 Claims priority, application Italy, Dec. 15,1962, 24,672/ 62 12 Claims. (Cl. 13971) This invention relates to adobby capable of reaching high working speeds, and therefore to be usedon speedy looms.

The problem of rendering speedy dobbies in general had till now noparticular consideration in the technique of weaving, because they weremostly used in conventional looms which are since the origin rattherslow in working. When but these devices were set up into speedy looms,they were to constitute a serious obstacle because of their low working,such as to require a heavy limiting of the working speed of said looms.The limited speed of said dobbies was mainly to be ascribed to theconcept by which their mechanical parts were designed and built, so asto provoke high accelerations of moving of the heddles, and further highfriction between the lever means themselves. As a matter of fact themovement of the sliding levers for the dogs was obtained by means ofoperating cams upon two angles of about 90 intersected by two restingangles, so as to compose an operating cycle comprising a step ofhoisting of the heddles, a resting step, then a step of lowering theheddles, and a resting step in lowered position. The succession of theseseveral steps of working and resting took place by means of very quickmovements of said heddles, what matter gave accelerations, and thereforeto considerable inertia of the same, so that an increase of speed waspractically impossible, inasmuch as said heddles were induced to skipinstead of to displace smoothly but quickly.

Further drawbacks hindering the quick movement of the dobbies were to beseen in the mode of lowering of the selected hooks, inasmuch as theylowered by the force of gravity, for which it was impossible to increasethe speed of movement. Still a further drawback was given by thetransmission of the movement of the hooks from the selecting knives,inasmuch as this operation took place by means of small bars in slidingcontact each with other, such that an increase of speed should havecaused a quick wearing of the hooks themselves. Another drawback was tobe ascribed to the engaging system of said hooks onto the dogs, due tothe fact that said hooks were built with an acute corner, which had toengage onto a corresponding acute edge of said dogs, for which thelasts, in order to be able to provide for said engagement wereconstrained to make a greater stroke in order to overgo the biasedportion of said hooks.

The dobby according to this invention eliminates all said drawbacks.

A first object of said dobby is represented by the fact that themechanisms for moving the dogs are provided with continuous movementswithout any resting intervals, such that the usually as resting stepsused phases are utilised for imparting to the dogs a more smoothmovement with a more smooth acceleration for which their drawing actiononto said hooks, and consequently onto the heddles, will take place witha lesser acceleration, and a considerable reduction of the force ofinertia, so that the frequency of the movements of the dogs will beconsiderably increased.

A further object of this invention is given by the fact that the patternwith fingers or in the form of perforated band is provided with anuninterrupted movement which is synchronised with the displacement ofthe dogs so as to act upon the selecting knives in anticipated periodsof time, thus providing the selected hooks to quickly lower and engagethe dogs, without any resting intervals for the lasts.

Still another object of the invention is to be found in the fact that inorder to increase the quick lowering of the hooks onto the dogs theselecting knives are controlled in such a way that the hooks arereleased and then lowered an instant before the respective dog willreach its dead point of engagement, so that the hook, before engagement,will rest upon the dog by sliding thereon and consequently will furtherengage the acting edge as soon as the same will be reached.

A further object of the invention is given by the fact that the bookends, as well as the bar ends, which have to act upon said hooks, areprovided with wear protecting means for the material subjected tofriction, f.i. in the form of rollers, smooth surfaces, or the like.

Still a further object of the invention is that the hooks are returneddownwards into the position of engagement by appropriate springs for asubstantial acceleration of their speed under the action of gravitytoward the dogs.

Still anotherobject of the invention has to be seen in the fact that theselecting knives are returned to a resting position by appropriatesprings which also aid the disengaging movement of said hooks.

Another object of the invention consists of the fact that the dogs arefitted on the extension in the oscillating side of a respectivearticulated parallelogram which is brought to oscillation between twosymmetrical positions in respect of the rectangular position of saidquadrilateral so as to substantially reduce the curvature of thetrajectory of said dogs.

Another object of the invention is ascribed to the fact that theengaging edge of the dogs and the hook corner of the hook levers aresustained in order to facilitate the engagement and in the same time toreduce the dog stroke.

A last object of the invention is the fact that along the trajector ofthe dogs protecting roofs are provided, under which the hook leversmove, and the purpose of which roofs is to prevent that the said hooksspontaneously disengage from the dogs.

The aforesaid and further objects of this invention are represented asan example of its embodiment in the attached drawings, of which:

FIGURE 1 is a dobby for controlling the dogs and the pattern shaft;

FIGURE 2 is a section of the center of the dobby with the controllingleverage of the hooks and the levers for the movement of the heddles;and

FIGURES 3 to 9 show diagrammatically several working steps of the dobbyof FIGURES 1 and 2.

Going back to FIGURE 1, from side wall 1 a drive shaft 2 projects, saidshaft being driven with a continuous rotating motion. Said shaft bearskeyed thereon two cams 3 and 4, each an eccentric circular disk,conveniently phase displaced to cause displacements of the phasedisplaced dogs to 180. The axes of the circular or annular peripheralfaces of cams 3 and 4 are parallel to and equidistant from the axis ofdrive shaft 2. On each one of these cams respective rollers 6 and 7 arepositioned. Roller 6 is disposed at the end of arm 8 forming with thearm 9 an integral lever body. Said lever arm 9 combines with a parallellever 10, and forms together with it and an upper rod 11, an articulatedparallelogram engaged with pivots 12 and 13, so that, owing to therotation of cam 3, said parallelogram oscillates in respect of thecentral rectangular position, and consequently rod 11 is submitted toalternate translations of small amplitude. At the extended end of saidrod 11 there is a dog 14,

which as shown, has a rectangular cross section with a right angleengaging edge 15.

In a same manner roller 7 is supported by an arm 8' connected to a leverarm 9 which, together with a parallel lever 10 and a transversal lever11, forms an oscill'ating articulated quadrilateral oscillating onrespective pivots 12' and 13'. At the free end of rod 11 there isapplied a second dog 14 with an engaging edge 15' of right angle. Alsoin this case the action of cam 4 on roller 7 causes an oscillation ofthe lever arms 9 and 10, and therefore a translating movement of smallamplitude of the rod 11'.

The phase displacement of cams 3 and 4 also causes the phasedisplacement of 180 of the dogs Hand 14', such that, when the one iswholly advanced, the other is wholly retracted, and vice versa.

As it may be seen on FIGURE 1 the reciprocating movement of the dogs 14and 14', in opposite strokes is continuous; that is to say, withoutresting steps caused by the cams.

The rotary continuous movement of a small shaft 16, whereon an endlessscrew 17, meshing with gear 18 is keyed on the pattern moving shaft 19so that said pattern will be advanced by a continuous, and not any moreintermittent movement as with the conventional dobbies, is transmittedonto shaft 2 by means of a transmitting device and an appropriate speedreduction transmission (not shown).

Behind'plate 1 a row of hooks is located, as shown in FIGURE 2, whereinonly a pair of them is represented in action upon a unique heddle.

Referring now to said FIGURE 2, draw hooks 20, 2t), respectively of theupper row of hooks, and of the lower one, have a rectangularly made hookedge in order to en sure a quick engagement onto dogs 14, 14'. The drawhooks are located on rectilinear rods or arms 21, 21', respectively,biased downwards by respective springs 22, 22. Rods 21, 21' arearticulated at the ends of a lever 23, known as a baulk lever anddisplaced by that hook which is brought to advance by the respective dogarticulated at the opposed end, said articulation taking place on tworesting points 24 and 25, alternately. In an intermediate position, saidlever 23 supports a pivot 26 to which a specially shaped lever 27,articulated at one end on a pivot 28, and having at the opposed free enda hook 29 connected through a link with a connecting rod 30 acting upona heddle in the known manner.

Said lever 27 therefore is displaced by the lever 23 following both themovements of the hooks 20 and 20, respectively and alternately,

The shaft 19, brought into continuous rotation by the gear 18 (FIGURE1), carries a pattern drum 31 mounted with the purpose of moving incontinuation a manufacturing pattern operating by means of operatingfingers. Said drum 31, or another equivalent pattern control device, mayalso drive in continuation a pattern in the form of a perforated paperband of a type known in the art.

In the actual case, the pattern drum 32 is provided with operatingfingers 33 and it acts upon a series of pairs of knives or followermembers 34 and 35, known per se, and pivoted on a common shaft 36, beingprovided at their lower portion of specially shaped cam profiles withwhich the fingers 33'of the pattern 32 cooperate.

Knives 34 and 35 are urged backwards by springs 37, 38, respectively,and at the front part the knife 34 acts upon a vertical hook needle rod39, whilst the other knife 35 acts upon a shorter also vertical hookneedle rod 40. Said vertical rod 39 has at its upper end a roller 41which acts upon the arm 21 of the hook 20. In the same manner theshorter rod is provided with a roller 42 by means of which the arm 21'of the hook 29' is actuated. Members 34, 35 constitute motiontransmitting means between pattern control means 32, 33 and the drawhooks.

The ends of hooks 20 and 20 are provided with respective rollers 43 and44 (FIGURE 1). These rollers serve to reduce friction of the contactingparts in movement such that notwithstanding the high speed of operatingno wear of these last mentioned parts will occur.

The disposition of the cam profiles of knives 34 and 35, and furthereven of the moving and continuous forwarding of fingers 33 are exactlysynchronised by the rotation of the eccentrically set cam wheels 3 and 4of FIGURE 1 so that the hooks are operated by the pattern 32 with therequired selection in manufacturing while the dogs, which are moved bysaid eccentric wheels, are submitted to their continuous alternatingmovement, without any resting interval, in order to ensure theirselection or disengagement in preceding times in respect of that of therear dead point of the dogs as it will be explained later. In front ofthe hooks 2t), 20, guiding strips 45 and 46, respectively, are providedat the underside of which the dogs travel, when moved forwardly, withthe view to prevent disengagement of said hooks.

FIGURES 3 through 9 refer to successive steps of operation of the dobbyof FIGURES 1 and 2, in operating with a double raising stroke.

In FIGURE 3 it is supposed that hook 20' has just been disengaged, whilehook 20 is raised, so that dog 14 has reached its rear dead point, anddog 14 is still in its front dead point. In this position, knife 34 isnot engaged by the finger 33, whilst knife 35 is still engaged by thefinger 33' which has lowered the small rod 40, thus permitting hook 20to fall onto the dog 14'. As cams 3 and 4 (FIGURE 4) continue to rotate,the dog 14' also continues to advance, thus trailing the hook 20 so thatit enters a position underneath the guiding strip 46, while dog 14freely relapses. Rod 23 oscillates, being fulcrated on the supportingmeans 24, thus also trailing in this movement the specially shaped lever27, as represented in FIGURE 2. Finger 33 almost contacts with theprofiled knife portion 34, while finger 33 still engages the profiledknife portion 35.

In the successive working step of FIGURE 5, due to the furtherforwarding of dog 14 and withdrawing of dog 14, the finger 33 hasadvanced so as to engage the profiled track of knife 34, thus causinglowering of the longer rod 39. Thus hook 23 instantly falls under thedrawing action of spring 22, as shown in FIGURE 2. At the same time dog14 has been displaced to a position in which said hook rests and throughroller 43 also travels thereon, thus assuming the position of selection,while dog 14' continues to advance.

In the working step of FIGURE 6, and continuing the rotation of theeccentric wheels 3 and 4, the dog 14' has reached its dead center on theright, thus controlling the largest displacement of the hook 20' and themaximum oscillation of the lever 23'pivoted on support 24.

At the same time, the dog 14- has moved to its rear dead centerposition, and-the hook 20, due to the action of spring 22, has lowered,thus'engaging the dog 14. Simultaneously, the fingers 33 and 33' havefurther advanced and contacted with the respective profiled tracks ofknives 34 and 35.

In the working step of FIGURE 7, wherein the eccentric wheels 3'and 4still rotate, the forward movement of dog 14 begins, thus trailing thehook 20, which engages underneath the guiding strip 45, thus alsocontrolling the displacement of lever 23 to the corresponding direction,so as to disengage from its support 24. In the same time the dog 14'begins its return stroke, thus tending to bring the lever 23 to rest onthe support 25. Simultaneously the fingers 33 and 33' are both stillcontacting with the respective profiled tracks of knives 34 and 35.

In the working step of FIGURE 8, the forward movement ofthe clog 14'andconsequently the advancing of the hook 24) has continued with theconsequent moving away of lever 23 from its support 24, while the dog14' continues to run backwards, so that the hook 20 will be broughtalmost out of the guiding strip 46, thus causing the lever 23 toapproach still more the lower support 25. In this position, finger 33 isstill in contact with the profiled track of the knife 34, whilst thefinger 33' is to abandon the profiled track of knife 35.

In the working step of FIGURE 9, the dog 14 has wholly advancedunderneath the guiding strip 45 and has thus caused the greatestdisplacement of the hook 20, thus obtaining maximum distance of thelever 23 from the support 24. In the same time the dog 14 has completedits return stroke, and caused the maximum return of the hook 20', thusbringing the lever 23 to rest on the support 25. In this position thefinger 33' has left the profiled track of knife 35, whilst the finger 33is still in contact with the profiled portion of knife 34. Consequently,in this position the knife 35, due to the action of the spring 38, canraise its free end, by raising the smaller rod 40 and together with itthe hook 20, disengage it.

Considering again the FIGURES 3 through 9, it appears evident that theuninterrupted and synchronised action of the several members, due to thetotal absence of resting intervals of the dogs, and further on accountof the according control ofthe lever 23, which is moved for the doublestroke of raising, its control pivot 26 is always held outside of theusual line of resting, so as to always maintain the heddle engagedthereby correspondingly raised in order to ensure the double raisingstroke thereof.

Of course, continuing the rotation of the wheels 3 and 4, a furtherselection step may take place, in accordance with the formation of thepattern strip 32 with an according development which will reflect thatof the preceding working steps.

It is evident from the FIGURES 3 through 9 that the trajectory of thedogs 14 and 14' constitutes a little accentuated curvature thusfacilitating a quicker operation of the dobby, a better performed actionof the guiding strips 45 and 46 in preventing the spontaneousdisengaging of the hooks, whilst the provision of supporting means forsaid dogs in the form of articulated quadrilaterals allows a much higherfrequency of the reciprocating strokes of said dogs.

Of course this invention is not limited to the embodiment shown hereinby way of a sole example of execution of its subject matter, andmodifications and variants are possible for people skilled in the artwithout going beyond the limitations stated in the following claims.

What we claim is:

1. A dobby comprising, in combination, a pair of dog means mounted forreciprocating movement along two paths; drive means for reciprocatingsaid dog means in opposite reciprocating forward and rearward strokes;baulk lever means mounted for oscillatory movement; a pair of draw hookmeans mounted on said baulk lever means for angular movement betweenfirst positions located in said paths of said dog means, respectively,and second positions spaced from said paths; and rotary pattern meansincluding periodically moving control means and motion transmittingmeans actuated by said periodically movable control means of said rotarypattern means and cooperating with said draw hook means for placing eachdraw hook means in said first position thereof during the forward strokeand also during the last part of the rearward stroke of the correlateddog means whereby the respective hook means is reciprocated by thecorrelated dog means and is already in said second position thereof whenthe correlated dog means starts the forward stroke thereof.

2. A dobby comprising, in combination, a pair of dog means; drive meansfor reciprocating said dog means in opposite forward and rearwardstrokes and including a drive shaft having an axis, a pair of drivemembers eccentrically mounted on said drive shaft and having annularfaces having axes parallel to the axis of said drive shaft equidistantfrom said axis, two parallelogram linkages, and a cam follower securedto each parallelogram linkage and in contact with said annular faces ofsaid drive members, respectively, each of said parallelogram linkagesbeing connected to one of the dog means so that the same arereciprocated along two paths; baulk lever means mounted for oscillatorymovement; a pair of draw hook means mounted on said baulk lever meansfor angular movement between first positions located in said paths ofsaid dog means, respectively, and second positions spaced from saidpaths; and rotary pattern means including periodically moving controlmeans and motion transmitting means actuated by said periodicallymovable control means of said rotary pattern means and cooperating withsaid draw hook means for placing each draw hook means in said firstposition thereof during the forward stroke and also during the last partof the rearward stroke of the correlated dog means whereby therespective hook means is reciprocated by the correlated dog means and isalready in said second position thereof when the correlated dog meansstarts the forward stroke thereof.

3. A dobby comprising, in combination, a pair of dog means; drive meansfor reciprocating said dog means in opposite reciprocating forward andrearward strokes and including a drive shaft having an axis, a pair ofdrive members eccentrically mounted on said drive shaft and havingannular faces having axes parallel to the axis of said drive shaftequidistant from said axis, two parallelogram linkages, and a camfollower secured to each parallelogram linkage and in contact with saidannular faces of said drive members, respectively, each of saidparallelogram linkages being connected to one of the dog means so thatthe same are reciprocated along two paths; baulk lever means mounted foroscillatory movement; a pair of draw hook means mounted on said baulklever means for angular movement between first positions located in saidpaths of said dog means, respectively, and second positions spaced fromsaid paths; rotary pattern means having two sets of control projections;and a pair of follower members connected with said draw hook means,respectively, for moving the same between said first and secondpositions, said follower members cooperating, respectively, with saidsets of control projections whereby said hook means are reciprocated bysaid dog means.

4-. A dobby comprising, in combination, a pair of dog means; drive meansfor reciprocating said dog means in opposite forward and rearwardstrokes and including cam means, two parallelogram linkages, and a camfollower secured to each parallelogram linkage and in contact with saidcam means, each of said parallelogram linkages being connected to one ofthe dog means so that the same are reciprocated along two paths; baulklever means mounted for oscillatory movement; a pair of draw hook meansmounted on said baulk lever means for angular movement betwen firstpositions located in said paths of said dog means, respectively, andsecond positions spaced from said paths; and rotary pattern meansincluding periodically moving control means and motion transmittingmeans actuated by said periodically moveable control means of saidrotary pattern means and cooperating with said draw hook means forplacing each draw hook means in said first position thereof during theforward stroke and also during the last part of the rearward stroke ofthe correlated dog means whereby the respective hook means isreciprocated by the correlated dog means and is already in said secondposition thereof when the correlated dog means starts the forward strokethereof.

5. A dobby comprising, in combination, a pair of dog means; drive meansfor reciprocating said dog means in opposite forward and rearwardstrokes and including cam means, two parallelogram linkages, and a camfollower secured to each parallelogram linkage and in contact with saidcam means, each of said parallelogram linkages being connected to one ofthe dog means so that the same are reciporcated along two paths; baulklever means mounted for oscillatory movement; a pair of draw hook means,each draw hook means including an arm mounted for angular movement atone end of said baulk lever means, springs connected to each arm, and adraw hook at the end of said arm, said draw hook means being urged bysaid springs to first positions in which said hooks are located in saidpath of said dog means and in which said arms abut said dog means,respectively, and having second positions spaced from said paths; rotarypattern means having two sets of control projections; and a pair offollower members connected with said draw hook means, respectively, formoving the same bewteen said first and second positions, said followermembers cooperating, respectively, with said sets of control projectionswhereby said hook means are reciprocated by said dog means.

6. A dobby comprising, in combination, a pair of dog means, each dogmeans having a pair of faces intersecting at a right angle; drive meansfor reciprocating said dog means in opposite forward and rearwardstrokes and including cam means, two parallelogram linkages, and a camfollower secured to each parallelogram linkage and in contact with saidcam means, each of said parallelogram linkages being connected to one ofthe dog means so that the same are reciprocated along two paths; baulklever means mounted for oscillatory movement; a pair of draw hook means,each draw hook means including an arm mounted for angular movement atone end of said baulk lever means, springs connected to each arm, and adraw hook at the end of said arm, said draw hook means being urged bysaid springs to first positions in which said arms abut one of saidfaces of said dog means and said hooks are located forwardly of theother face of the respective dog means and in said path of said dogmeans, respectively, and second positions spaced from said paths; rotarypattern means having two set of control projections; and a pair offollower members connected with said draw hook means, respectively, formoving the same between said first and second positions, said followermembers cooperating, respectively, with said sets of control projectionswhereby said hook means are reciprocated by said dog means.

7. A dobby comprising, in combination, a pair of dog means; drive meansfor reciprocating said dog means in opposite forward and rearwardstrokes and including cam means, two parallelogram linkages, and a camfollower secured to each parallelogram linkage and in contact with saidcam means, each of said parallelogram linkages being connected to one ofthe dog means so that the same are reciprocated along two paths; baulklever means mounted for oscillatory movement; a pair of draw hook meansmounted on said baulk lever means for angular movement between firstpositions located in said paths of said dog means, respectively, andsecond positions spaced from said paths; rotary pattern means having twosets of control projections; and a pair of follower members connectedwith said draw hook means, respectively, for moving the same betweensaid first and second positions, said follower members having cammingfaces cooperating, respectively, with said sets of control projectionsfor placing said draw hook means are placed in said first positionduring the forward stroke, and also during the last part of the rearwardstroke of the correlated dog means whereby said hook means arereciprocated by said dog means and are already in said second positionwhen said dog means start the forward stroke thereof.

8. A dobby comprising, in combination, a pair of dog means; drive meansfor reciprocating said dog means in opposite forward and rearwardstrokes and including a drive shaft having an axis, a pair of drivemembers eccentrically mounted on said drive shaft and having annularfaces having axes parallel to the axis of said drive shaft equidistantfrom said axis, two parallelogram linkages, and a cam followier securedto each parallelogram linkage and in contact with said annular faces ofsaid drive members, respectively, each of said parallelogram linkagesbeing connected to one of the dog means so that the same arereciprocated along two paths; baulk lever means mounted for oscillatorymovement; a pair of draw hook means, each draw hook means including anarm mounted for angular movement at one end of said baulk lever means,springs connected to each arm, and a draw hook at the end of said arm,said draw hook means being urged by said springs to first positions inwhich said hooks are located in said path of said dog means and in whichsaid arms abut said dog means, respectively, and having second positionsspaced from said paths; and rotary pattern means including periodicallymoving control means and motion transmitting means actuated by saidperiodically movable control means of said rotary pattern means andcooperating with said draw hook means for placing each draw hook meansin said first position thereof during the forward stroke and also duringthe last part of the rearward stroke of the correlated dog means wherebythe respective hook means is reciprocated by the correlated dog meansand is already in said second position thereof when the correlated dogmeans starts the forward stroke thereof.

9. A dobby comprising, in combination, a pair of dog means, each dogmeans having a pair of faces intersecting at a right angle; drive meansfor reciprocating said dog means in opposite forward and rearwardstrokes and including a drive shaft having an axis, a pair of drivemembers eccentrically mounted on said drive shaft and having annularfaces having axes parallel to the axis of said drive shaft equidistantfrom said axis, two parallelogram linkages, and a cam follower securedto each parallelogram linkage and in contact with said annular faces ofsaid drive members, respectively, each of said parallelogram linkagesbeing connected to one of the dog means so that the same arereciprocated along two paths; baulk lever means mounted for oscillatorymovement; a pair of draw hook means, each draw hook means including anarm mounted for angular movement at one end of said baulk lever means,springs connected to each arm, and a draw hook at the end of said arm,said draw hook means being urged to said springs to first positions inwhich said arms abut one of said faces of said dog means and said hooksare located forwardly of the other face of the respective dog means andin said path of said dog means, respectively, and second positionsspaced from said paths; and rotary pattern means including periodicallymoving control means and motion transmitting means actuated by saidperiodically movable control means of said rotary pattern means andcooperating with said draw hook means for placing each draw hook meansin said first position thereof during the forward stroke and also duringthe last part of the rearward stroke of the correlated dog means wherebythe respective hook means is reciprocated by the correlated dog meansand is already in said second position thereof when the correlated dogmeans starts the forward stroke thereof.

10. A dobby comprising, in combination, a pair of dog means, each dogmeans having a pair of faces intersecting at a right angle; drive meansfor reciprocating said dog means in opopsite forward and rearwardstrokes and including cam means, two parallelogram linkages, and a camfollower secured to each parallelogram linkage and in contact with saidcam means, each of said parallelogram linkages being connected to one ofthe dog means so that the same are reciprocated along two paths; baulklever means mounted for oscillatory movement; a pair of draw hook means,each draw hook means including an arm mounted for angular movement atone end of said baulk lever means, springs connected to each arm, and adraw hook at the end of said arm, roller means on said draw hooksadapted to roll on one of said faces of said dog means, said draw hookmeans being urged bysaid springs to first positions in which said armsabut one of said faces of said dog means and said. hooks are locatedforwardly of the other face of the respective dog means and in said pathof said dog means, respectively, and second positions spaced from saidpaths; rotary pattern means having two sets of control projections; anda pair of follower members connected with said draw hook means,respectively, for moving the same between said first and secondpositions, said follower members cooperating, respectively, with saidsets of control projections whereby said hook means are reciprocated bysaid dog means.

11. A dobby comprising, in combination, a pair of dog means; drive meansfor reciprocating said dog means in opposite forward and rearwardstrokes and including cam means, two parallelogram linkages, and a camfollower secured to each parallelogram linkage and in contact wtih saidcam means, each of said parallelogram linkages being connected to one ofthe dog means so that the same are reciprocated along two paths; baulklever means mounted for oscillatory movement; a pair of draw hook meansmounted on said baulk lever means for angular movement between firstpositions located in said paths of said dog means, respectively, andsecond positions spaced from said paths; rotary pattern means having twosets of control projections; and a pair of follower members and a pairof hook needle rods connected with said follower members, respectively,and having roller means in contact with said draw hook means,respectively, for moving the same between said first and secondpositions, said follower members cooperating, respectively, with saidsets of control projections whereby said hook means are reciprocated bysaid dog means.

12. A dobby comprising, in combination, a pair of dog means, each dogmeans having a pair of faces intersecting at a right angle; drive meansfor reciprocating said dog means in opposite forward and rearwardstrokes and including a drive shaft having an axis, a pair of drivemembers eccentrically mounted on said drive shaft and having annularfaces having axes parallel to the axis of said drive shaft equidistantfrom said axis, two parallelogram linkages, and a cam follower securedto each parallelogram linkage and in contact with said annular faces ofsaid drive members, respectively, each of said parallelogram linkagesbeing connected to one of the dog means so that the same arereciprocated along two paths; baulk lever means mounted for oscillatorymovement; a pair of draw hook means, each draw hook means including anarm mounted for angular movement at one end of said baulk lever means,springs connected to each arm, and a draw hook at the end of said arm,roller means on said draw hooks adapted to roll on one of said faces ofsaid dog means, said draw hook means being urged by said springs tofirst positions in which said arms abut one of said faces of said dogmeans and said hooks are located forwardly of the other face of therespective dog means and in said path of said dog means, respectively,and second positions spaced from said paths; guide means along saidpaths for guiding said draw hooks while located in said paths topositions in which said arms abut said dog means; rotary pattern meanshaving two sets of control projections; and a pair of follower membersand a pair of hook needle rods connected with said follower members,respectively, and having roller means in contact with said draw hooksmeans, respectively, for moving the same between said first and secondpositions, said follower members cooperating, respectively, with saidsets of control projections whereby said hook means are reciprocated bysaid dog means.

References Cited by the Examiner UNITED STATES PATENTS 1,514,873 11/1924Staubli 139--7l 2,071,784 2/1937 Edwards l3974 X 2,644,48 8 7/ 1953Pfarrwaller 1397l X 2,646,080 7/1953 Kronolf 13968 3,057,379 10/1962Staubli 139--71 FOREIGN PATENTS 538,616 3/1922 France.

15,979 18 84 Great Britain.

862,666 3 1961 Great Britain.

886,310 1/ 1962 Great Britain.

9 14,481 1/ 1963 Great Britain.

330,439 7/ 8 Switzerland.

DONALD W. PARKER, Primary Examiner.

1. A DOBBY COMPRISING, IN COMBINATION, A PAIR OF DOG MEANS MOUNTED FORRECIPROCATING MOVEMENT ALONG TWO PATHS; DRIVE MEANS FOR RECIPROCATINGSAID DOG MEANS IN OPPOSITE RECIPROCATING FORWARD AND REARWARD STROKES;BAULK LEVER MEANS MOUNTED FOR OSCILLATORY MOVEMENT; A PAIR OF DRAW HOOKMEANS MOUNTED ON SAID BAULK LEVER MEANS FOR ANGULAR MOVEMENT BETWEENFIRST POSITIONS LOCATED IN SAID PATHS OF SAID DOG MEANS, RESPECTIVELY,AND SECOND POSITIONS SPACED FROM SAID PATHS; AND ROTARY PATTERN MEANSINCLUDING PERIODICALLY MOVING CONTROL MEANS AND MOTION TRANSMITTINGMEANS ACTUATED BY SAID PERIODI-